Internal-combustion rotary motor



y 1,619,237 March l,-l927. G. E. BRAGG INTERNAL COMBUSTION ROTARY MOTOR Original Filed July 25, 1919 3 Sheets-Sheet l Y. 1 h 1,619,237 March 151927' E, BRAGG INTERNAL COMBUSTION ROTARY MOTOR Original Filed Jy, 1919 5 SheetsfSheet 2 42/420 60 6/ y n 3443 4 if Y l "d E@ 66 Q 5 [El A211/ E? @e n /9 z f ,f 64! 60 1,619,237 March l, 1927. G. E. BRAGG INTERNAL COMBUSTION lRTARY MOTOR Original Filed July 25, 1919 3 Sheets-Sheet 5 Patented Mar. 1, 1927.

PATENT este,

GEORGE EDGAR BRAGG, 0F CINCNNATI, OIIIO.

INTERNAL-COMBUSTION ROTARY MOT-.

i Application led July 25, 1919, Serial No. 313,353. Renewed November r29, 19219:.'

My invention relates to a nove-l type of internalv combustion rotary motor wherein the cylindersare mountedV fast on a'central shaft and are provided with pistons carrl ing at their outer ends rollers which contact with specially designed cam tracks so disposed and arranged as to utilize the thrust of the pistonsagainst them to rotate the cylinders.

fOne object of my invention is to design the engine Witha cylinder Within which tivo opposing pistons Work, which pistons are arranged to co-act with cam tracks so designed that I obtain in effect a three stroke cycle motor, since during each cycle the first stroke will carry both pistonson the power oper-ation together, the second stroke Will hold one piston While moving the other on the scav enging operation, and the third stroke Will move the pistons together to effect the compression operation, y thus completing the cycle. In other Words, the pistons considered as a unit have performed the three foregoing separate and distinct operations during each cycle, notwithstanding the fact that each of the pistons individually completes only tivo strokes. 1n itsl preferred design the engine proper comprises two cylinders each offset from the engine center and arranged in parallelism, and each provided With its pair of co-acting pistons Which complete the three stroke cycle operation abovedescribed.

A further object is to provide an auto-r matic piston valve responsive in its action to the compression ofl air at the extreme outer stroke of the pistons of adjacent cylinders and movable thereby into position tc bring the exhaust ports ofthe cylinder, previously in communication With the mix-- ing chamber, into communication with the atmospheric exhaust for Y carrying off the gases. I f

n further feature of my invention is the manner of balancing'the Working pressure in all'cylinde-rs by having them in free com-y munication at theirinner ends and so controlling and timing the movement of their pistons aste cause a piston ofeach cylinder at thesaine til-neto stand at lthe outer endL of its stroke holding exhaust ports open-4 Wliile rthe'opposing*two pistons are moving to scavenge'the cylinders. Y

, Afurther obiect of my vinvention is to provide all the cylinders with a common lcentral explosion chamber into which the @com-V, pressed air, driven into themixing chamber Vby the power stroke of the pistons, Will be automatically discharged through pressure controlled valves as soon as the gases are exhausted from the cylinders and the pressure therein has dropped sufficiently to perf mit the compressed air in the mixing chamb er to open the valves and enter thev commonV ydrowcarbon'series, but if ofthe heavier oils to deliver it into spray nozzles or injectors `in the mixing chambers which are controlled by the piston valves so as to inject the oily spray after the scavengingoperation in the combustion chamber.`

A further object is to cause Y pressure in the cylinders' to be exerted through theirpiston rollers onjthe zones of maximum inclination in vthe cam tracks, thus most efficiently converting the ypiston energy into a rotary drive for the motor.

A further: object of my invention is to arrange the rotating motor in a casing having ample air vents in its side walls so that the radiatingfins with which the cylinders are provided Will serve to air cool them.

It is Within the contemplation of my invention that a series of such units may have their respective shaft-s coupled for lioint operation, beingtproperly set to bring their firing points at the proper relative angle-s about the shaft center in accordance With` controlling the intake,` compressionand `exsl haust of air in theyoutejr ends of the cylinders in a radically novel mannen The air compressed by the pistons power stroke 1s,

forced past suitable valvemeans into a mixing chamber ateach end of the motor and these chambers have inwardly opening air supply valves andou'twardly opening valves` for admitting `air to the cylinders, which the highest" `valves allrespondKV automatically to the: ac-

tion of the pistons. o Y o 1t is a further object to so designH the curved tracks vvhich are engaged by .the piston "rollersthat `they pref sentrzones of maxi-mum inclinationto the of' my invention rollers of pistons that are exerting their maximum power' stroke and zones of relatively low inclination to the rollers ot pistons during their compression strokes. By this arrangement my motor attains the maximum eiieiency in the conversion ot` radial and rotary movement trom stator to rotor and accomplishes with the least possible angular strain the inward movement of the pistons to etlect the requisite compression. y

One of the most important objects oi my invention is to produce a flexible. low speed motor suitable for general purposes without the sacrifice of power and compactness. this end my motor is adapted7 with the saine piston displacement of the present motor types, to attain only twenty-five per cent ot their maximum Speedster a given power output, this being obtainable beca use the two opposite pistons in each cylinder will double the pistons travel during one stroke and my motor is designed to have two power strokes for every revolutionA` thereby enabling it to produce four times as much piston travel in one revolution as would be obtainable in the present general type of motor. y It 'tollows therefore that it is capable ot attaining maximum piston travel in one-lourth as many revolutions i and the minimum speed attainable is reduced proportionately. Moreover, by reason of `the tact that my motor is designed to utilize the high cylinder pressure during the best working angle of the stroke, or `in other Words maximum piston speed being at the beginning ot the stroke, enables the piston to displace the rapid rise in pressure during eomliustion. whereas in the present type of motor the minimum piston speed, whichis comparatively very slow at the beginning of the piston stroke gradually increases as it `approaches its best working angle, thus malring it necessarv for the motor to attain considerable speed before thepiston is moving v fast enough to displace the rapid expansion of combustion so as to eticiently utilize the power thereof. The advantages ot construction areobtainable Without regard to which of the co-acting general elements is regarded as the rotor and which the staten It is a further object of my invention to so design the curved tracks that the dead Center positions of the pistons with reference thereto, `are unequally spaced to the end that the piston shall be caused to coniplete its power stroke in the traverse of the shorter zones between dead center positions and to complete its return through the longer zones. The shorter or power zones may represent an arc as small as 60O as compared with an arc of 1200 for the exhaust and compression zones, this arrangement making it possible to cause the pi.'- tons to co-act with the track with maximum eiliciency and with maximum lineal travel in the cylinders, and hence maximum displacement, whereas the slow return provides ideal conditions tor the exhaust, scavenging and compression operations.

M v invention also comprises the various novel details ot construction and arrangements ot parte, which in their preferred embodinicnt only are illustrated in the accompanyinpl dra wings, in which Fig.` 'l is a side elevation of a rotary ene'ine embodying my invention.

iipg. i). is a transverse sectional on the line .--Q of Fig. 3.

Fig. 3 un enlarged transverse sectional view taken on the line l-'l oi Fig. 5, showinethe rotor element only.

Fig. l is a sectional view enlarged ot they motor taken on the line -l--l ot Fig. -l.

Fig. 5 is a partial sectional and partial plan view taken on the line ot Fig. 6.

Fig. is a sectional view enlarged taken on the line (S-li ot' Fig.

Fig. 'T is an end view `in detail ot the vic taken `rotating motor element.

integral withtlie base lugs El by which the caf-'ing is anchored to its tomidation. Pret erably also each side wall has cast integral therewith a `cam track oblong in character and comprising` diametrically opposite double track sections i curved" inwardly troni the periphery to the diametrically opposite points oi maximum comp.' 'sion for the pistons will be laterdescribed,` and at that point the two tracks diverge,` one forming opposite outwardly curving tracks 5 .`n'l1ich are spaced 'further from the side wall than the other tracks which comprise opposite concentric sections ti and outwardly curved sections i', the sections T being similar in shape but advanced relatively to the outer track sections o. lt will be understood that each side wall .2- carries similar diamctrically opposite track sections l. 5, G and 'i' 'which are symmetrically disposed.

'.lhc side wills 2 have Asuitably mounted therein axles 8 provided at their inner ends with `ilaiig'cs 9 er) which are bolted to the side `spiders or `webs l0 which are integral with or suitably connected to the cool y onterendsot the cylinders 11 and 'l2 (Fig.

and stand clear et' `the radiating tins '1.3

snrroumling.the cylinders so 'as to permit a.

tree circulation `of air about them through llt) ` pistons.l

the large Ventilating ports 14 provided inthe casings sidewalls. The center line of the axle passes midway between the centers of the cyliiiders' which are closed at their outer ends by a cylinder head 15 carrying a. stuitinigebox 13 tlrrouglr which its respective pist0n rodl? passes. Preferably the adjacent hea-ds are cast in pairs for rigidity of struc'- ture. Each piston rod is suitably connected at its inner/end toa piston 18 which reciprocatesl in one end of its respective cylinder, thus providing what for facility of description. I may term four cylinders A, A', B, and BQ The cylinders A and B are ends ot the motor', leaving the cylinders A and B the other ends ot the motor and between these pairs of cylinders is arranged a pressure equalizing combustion chamber 19 opening at its ends intothe cylinders opposite the closure between the vpistons at their lextreme compression strokes. A. spark plug 20 is disposed to opera-te in the combustion chamber 19 and adapted to ignite the entire compressed charge of gas between the tour Insulated sparking circuits 21 for the plug lead through one ot the axles 8 while a fuel' oil feed pipe 22 leads through the other axle and by a by-pass'23 enters the injectors 24 which haveeach a spray nozzle 25 projecting through thel inner wall ot the chamber 34 and adapted to spray the Jfuel linto the combustion chamber 19. Each cylinder A. A. B and B is provided near its outer end with -a series of exhaust ports-26 and at Vits extreme outer end with an air port Q7. Thel air ports-27 of the cylinders A and B are connected by a by-pass 28, showny in dotted lines Fig. 3 and plan. Fig. 6,

and by this arrangement the final discharge of air from the cylinderv B will pass to cylinder A and thence flow thro-ugh a passage 29 to the onter end of cylinder 30 and in like manner the air will flow from cylinder B to A and lthence through the passage Q9 to the l' the pistons V18 in compressedl symmetrically arrangedV cylinder y3() at vt-he other end ot the motor. The air pressure createdl by thepistfrns after passing the exhaust ports 26 will thus become effective in each cylinder 30 upon a piston 31 there-in which is connected4 by stem 32 to a piston valve disposed in each 'chamber 34 and workingr therein as a cylinder so as to pass to' one side or theother ot vthe exhaustports Q6V which openrjiuto Such cylinden YVVVith Vposition-,V the ends `of their pistons 31 stand at the outer respective Icylinders in direct communicationwith the chambers 34. As the pistons move outwardly the air Vbehind themiis forced through these ports 26y and compressed in the' chambers 34 until the pistons passftlieports 26, whereupon the air is forced through the passagewaysQS and Q9 and the lpressure rises placing the pistons 31 and shitting the valves at adj acentV 30.' leaving the ports 26' in the cylinders 30 dis-l j j Y andwill therefore not interfere with the vot the valve 33 will operate a plunger 36 in each injector and will spray oil into the combustion chamber 1%). As soon as the exhaust of gases takes place the pressure in the chamber 19V is relieved. and the compressed air in the cham-bers 34 will open air valves 37 which are held normally closed by the action of spring 38. Each chamber 34 is provided with an inwardly opening' automatic intake air valve 39 (see Fig. 4) having a valve stem 40 urged by a spring 41 to closed position and which is adapted to be sucked openv by the inwardstroke of the pistons which suction is effective through ports 26 tol chambers 34 after the lpiston valves 33 have moved to their outer position in response to both suction and centrifugal torce. It is to be noted thatas the pistonvalves are moved inwardly by pistons 31they will turther compress the already com-pressed air in the chambers 34 and this air pressure will bring the pistons to rest about thre-edotu'iihs vof their full inward stroke. lThis partial spring 42 is interposed between each s-tem 43 on the piston 33 which telescopesjin the plunger' 36V so as toabsorb this partial movement,.but as soon as the exhaust ot gases has dropped/the pressure inthe chamber 19 low enough for thevalves Y3'? to open, the pressure'in chambers v34 will drop to atmosphere and the piston valves arev then free'to com-y plete their stroke. in doing' which the stems 43 will engage the plungers 36 and movethem to spray a charge of oil along with the air enteringpast valves 37 into vthe'combustion chamber. Before this occurs, however7 it is important to note that anample volume-v of air will have previouslyy passed valves 37 andlscavenged the combustion chamber 19 to the cylinders. Y

I'twill be noted, especially by reference to Fig; 3, that the piston valves 33 .are each provided with a curved rearvs-'ard-lyY inclined de ythey will'be discharged at considerable lvelocitylthrough the exhaust portsiin Vav rearward directionso as `to assist in propelling the rotating motor, It willt also be noted ward or'atinosp'heric exhaust position, this detlector 44 will drop below the exhaust port llO iso

ltl

plunger stent lil i rush ot` air induced by the notion ol? the rotor through the substantially circular ex-` haust port i but will cause the exhaust gases to be diverted in the direction of the liow ot the `air so as not onlvnot to retard the latter but to appreeiahtv augment it. This through dra'l't of air materially assists by a suction etl'eet in the scaveliging ol thel cylinders. The webs lo, which interrlnit the exhaust port, are lnore clearly shown in Fig. l` and in each ot' these I provide a longitudinal slot lll in which a guide tongue l-T on an extension i8 ot the piston 3l, works and prevents the piston valve lil turning the out of alignment with the injector. p

Each piston rod 17 at its outer end is connected to a volte shaped cross arin 4l) which at its outer ends is turned totorni bearings for the rollers 5() or `The cross arins on the piston rods ttor the cylinders A and A are shorter than the cross arms i'or the pisl tons in cylinders P and ll and the rollers on the short arn'is are designated o() and on the long arlns 5l. It will he seen that the dian'ietrically opposite cross arn'is are alike and this keeps the rotor in balance. The rollers 5l will travel on the inner tracks adjacent to the side walls 2 ol. the stator casing and the rollers 5() will travel on the inside or spared tracks In other words, the tracks 'for the rollers 51 are composed of the cam sections l, 5 and the intervening portions ot the easing rinn` representing concentric track ser The several rollers are mounted on anti-friction roller bearings 52 and the)T travel between the cani tracks as an outer bea ring and 'fixed guide tracks 3f-l as an inner bearing. This cain ltrack opposite the track sections marked 54 is provided with a concave section on which the rollers 5l travel, while it is provided with a continuous s vnnnetrioal convex section 56 on which the rollers travel. The concave section is necessary for `the wheels 5l to pass the point onthe outer cani. but this isnot needed t'or the wheels() as the latter will travel on the cani track 5 at this point. but if for any reason the pistons connected to the rollers o0 should not nlove ontwardlv following the cam traele this convex port-ion will ride theni past the concave and thus prevent them dropping thereinto and locking the motor. The civlinder heads carriv winglike "extensions 5T which are partlv sup` ported by the side walls of the cylinders il() and are providcdwitl'r flat parallel guide laces #i8 along which shoes 59 on the cross arms travel. These slides in reality constitute thrust blocks which transmit the lateral thrust from the cani tracks to the niotor as the rollers are" driven thereby and thevnlso serve to take the lateral strain otl piston rods and prevent the cross arnis and pistons from turning.

The lubricating system consists in an oil inlet :port provided by the central bore 60 in an axle 8 through which the fuel oil pipe passes. The lubricating oil entering the bore (il) isdiverted through passages 6l in the spider `Il() (see Fig. 4)and enters the chambers 3ft and it passes thence to the outer end of said chambers .in response to centrifugal pressure and its inertia. and enters the inner end ot the cylinder -lOthrough a port (S2 and thence passes through the exhaust ports 2G in the outer ends oi the motor c vlinders and thence passes through the passages to the outer end of the cylinders 30, thus luln'ieatingthe pistons 3l. Also spring pressed ball check valves ($3 will admit the oil under predetern'iined )jiressure to enter duets (il, each ot' whiclratits opposite ends enters the stutling boxes lll for the adjacent piston rods. These stntling boxes are provided with an annular oil ring or groove and the piston rods at their inner ends are provided with luln'icating passages 65 leading' therethrough and radially through their pistons to an oil ring groove (al surrounding each piston. These passages at the outer ends ol the piston strokes will register with the oil grooves GT in the stalling boxes 1G and thus a supply ot oilunder pressure will he t'orccd to the piston rings. Should there be a tendone)7 for either diagonally opposite pair ot cylinders to take too inuch oil, the ports (i5 for the pistons oil such c vlinders can? beset slightly :further from the pistonsv` thus causing them to pass bevond the oil grooves (37 in the stulling boxes to a greater or less extent and thusto nlodiiv the interval ol` register and the vohnne ot'foil fed. Bump# ers ($8 are. provided at the outer ends of the cvlindersieltl for the pistons 3l. to rest on.

The operation oiinrv invention will be better "understood by reference to the diagrammatic views shown. in Figs. S to l2 where the cylinders are appropriately designated and shown in their ating positions. Starting with the pistons at firing point the rollers are all in position readyto ride down their respective cani tracks and 7,-and it will he noted that the valves 37 are closed and the valves 33 are in position to throw the cylinders in eo1n1nunication with the chambers Bil. As the explosion takes place `theurollers are thrust down the cani` tracks 5 and 'l' at their point ol principal opermaximum inclination and in doing .so the motor is `shifted to the `position shown in Fig. 9 and then infFie'. l0 which complete its power stroke. ln the position, Fig.` il; the inotorpistons have closedthe exhaust portsfinto thechauibersldr andere beginning' to `compress air against the valve pis tons. At the conn'iletion ot the po wer strokc,' Fig. l()` the compressed air 'troni each pair oli cylinders has acted to shift the adjacent piston 3l its full stroke, thereby opening 13 the exhaust fromthe cylinders to the atmosphere and forcing first the compressed alii` and then the oil spray into the combustion chamber. vIn the short cycle of movement between the positions in Figs. l and 11, it will be observed that the .cam track 4 will shift the pistons in the cylinders B, B in- Wardly in advance of the pistons in .the cylinders A, A', thereby scavenging the cylin- Y the pistons to co-act withsaid cam tracksl fil ders and forcing out the burnt gases. The pis-.tons in the cylinders A and A are shifted quickly enough to close the exhaust ports before the escape of the mixture and the motor is then ready to assume the final position of its cycle shovvn in Fig. l2, in which all pistons are being forced inwardly to full compression positions shown in Fig. 8.

.It Will be understood that my invention may be modified in various particulars .Without departingfrom the novel principlesof construction and design which form the essence of my invention and I therefore do not desire to be limitedto the detail structure shown. `For instance, iinid pressure may be used to drive the motor instead of the explosive mixture.

Having thusdescribed my invention, what I claim as new and desire to secure by Letters Patent, is

l. In a rotating cylinder engine, a stator having cam tracks, a rotor having` a pair of parallel cylinders communicating :at their middle across the rotor center, two oppositely moving pistons in each cylinder, rollers on the pistons adapted yto co-act With said cam tracks substantially as described. and means to supply motive iuid to and exhaust it from said cylinders.

2. In a rotating cylinder engine, a stator having cam tracks, a rotor having cylinders `i offset from its center and provided yeach with a pair of opposing pistons, rollers on the pistons toV co-act with said cam tracks, and means to supply motive iiuid to .and exhaust it from said cylinders, said cam havmg zones of maximum inclination opposite the piston rollers as they start their power stroke. f

3. In a rotating cylinder engine, a `stator having cam tracks, a rotor having cylinders oflset from its center vand provided .each with a pair of opposing pistons, rollers .on

vmeans to supply motive fluid to land exhaust it from said cylinders, said cam tracks having zones of maximum inclination opposite the piston rollers as they start their power stroke, and slide bearings on the rotor to take the side thrust Vstrain on the rollers.

4. In a'rotating cylinder engine, a plurality of offset Vparallel cylinders communicating near their centers, a pair of oppositely moving pistons in each cylinder, rollers on Athe outer ends ofthe pistons, anda substantially elliptical track co-acting with :the

rollers and having zones of maximum inclinationy disposed to engage the rollers during their maximum novver stroke. V5. A rotating cylinder engine as defined in claim l having ,the poWer zones of the tracks inclined in the direction of the piston thrust, such inclination being maximum at thebcginning of the strokeand formed by `abrupt outwardly sloping surfaces which return by'gradual curves to the track of the rollers in full extended position.

.6. A rotarv cylinder engine comprising a rotor having a cylinder provided With a pair of opposing pistons and rollers on the pistons, anda stator comprising a cam track having concentric and eccentric curves disposed to be simultaneously engaged by said piston rollers during the exhaust scavenging intake and compression operation. V 7. A rota-ry cylinder engine comprising a rotor having a cylinder offset from the rotor center and provided vvith a pair yof. opposing pistons and rollers on the pistons, and a rstator com rising a cam track having .con-

centrican eccentric curves disposed to be simultaneously engaged by said piston rollers. i

k8. In rotary cylinder engine, a stator comprising a symmetrically curved cam track comprising eccentric and concentric curved portions, and a rotor comprising two offset cylinders, each having a pair kof 4OppirSed pistons, said cam track being arranged to cause diametrically opposite pistons of diierent cylinders to co-aot with similar opposed portions of the cam.

9. A rotary engine comprising a stator having cam surfaces and a plurality of ostfset cylinders therein, a common equalizing chamber having air and gas intakes Yand sparking means, the pistons for the cylinders having rollers co-acting With said cam surfaces, the cylinders being closed at their outer ends, and exhaust means for the cylinders automatically controlled by the air ompression inthe outer ends of the-.cyliners.

10. A rotary engine according to .claim 9, in which the outer ends of adjacent cylinders are connected, and .a common exhaust valve is provided for each connected pair of cylinder ends and controlled' by the joint air pressure created therein.

ll. An internal combustion rotary engine according to claim l, in which the camtracks are symmetrical andv comprise each opposing pairs ofV adjacent diii'erently curved Surfaces adapted respectively to be simultaneously engaged by the rollers of adjacent-.pistons as they complete their power strokes, and the like cam surfaces engaged by one pair of diametrically oppostepistons being concentric With the rotor While the cam surfaces'engaged by the other pair of pistons being eccentric to the rotorand adaptloo edto allow said latter' pistons to complete a return scavenging stroke before the other pistons close the exhaust.

12. In a rotary internal combustion engine, a stator comprising cam ways, a rotor comprising a plurality of cylinders having pistons, rollers at theouter ends of said pistons engaging said cam Ways, exhaust ports for the cylinder, chambers into which said exhaust ports open and Which have an atmospheric exhaust port, an automatic piston valve controlled by the centrifugal force and air pressure at the outer end of its respective motor cylinder and movable thereby into one position to bring said exhaust ports into comn'umication, an automatic internally opening air admission valve for each chamber, an outwardly opening air exhaust valve leading from each chamber into the explosive end ot its respective cylinder, `and means to supply fuel to and to ignite it in the cylinders.

13. An internal combustion rotary engine comprising a stator having cam tracks, a rotor com rising parallel `otl'set cylinders closed at tieir outer ends` and communicating at their middle portions, rcciprocable pistons in the ends `of said cylinders, rollers on the outer ends ot the pistons and adapted to engage said cam tracks, and automatic means to scavenge and recharge the cylinders, substantially `as described. y

14. A rotary internal combustion engine comprising a stator, a rotor providedwith offset cylinders having pistons with' rollers on the exposed ends of the pistons, means to close the outer ends of the cylinders, and an exhaust port for the cylinders having a free draft opening therethrough parallel with the plane of rotation of the rotor.

15.VA rotary internal coniiiustion engine according to claim 14, .in which a common exhaust valve provided tor the adjacent ends ot cylinders on the same side of the rotor and ,is designed With a detiecting surface disposed to direct the exhaust gases in the direction of flow of air through its respeetive exhaust port. y

16. A rotary motor as described in claim 1, in which the cam tracks comprise concentric curved portions adapted to hold through a predetern'iined an gulartra vel part ot the pistons engagingthcm at the extreme inner and part at the extreme outer ends of their stroke. i

17. A rotary internal combustion engine comprising a stator having cam Ways. a rotor having cylinders arranged in opposite pairs closed at their outer ends, pistons in `the cylinders having the piston rods projecting through the closed outerends ot the cylinders, rollers on said piston rods coacting with the stator cam ways; a chamber between each pair of cylinders having a cylinder at its outer end, an intermediate.

exhaust `port and a piston valve chamber near its inner end; a piston movable in said latter cylinder, and an exhaust valve connected to said latter piston, exhaust ports leading from near the outer ends ot adjoining motor cylinders into the adjacent valve chamber, ports leading from the outer ends of the adJaccnt chambers to the outer end ci the valve piston chamber, an automatic suction operated intake air valve for said chamber, a pressure controlled outlet valve opening from said chamber into the inner ends ot its adjacent motor cylindersand means controlled by the movement of the eX- haust valve to admit fuel to its respective motor cylinders, substantially as described.

18. A rotating internal combustion engine comprising a stator having cam Ways and cam surfaces, a rotor having cylinders closed at their outer ends, pistons therein and rollers connected to the pistons and coacting with said cam surfaces, means to introduce oil into the rotor and conduct it to the outer ends of the cylinders to lubricate said pistons, and pressure controlled means to feed the oil from the outer ends ot the cylinders to the Working surfaces ol the pistons, substantially as described.`

19. In a rotary cylinder engine, a stator having cani tracks, a rotor having parallel oiset cylinders closedat their outer ends and connected at their centers across the rotor center, pistons in the cylinders, and

bearings 0n the pistons which to-act with the stator cam tracks, substantially as described.

20. A rotary cylinder engine as described in claim 13, in which the air, gas and spark-- ing elements enter a chamber connecting thc middle portion of the cylinders.

21. A rotary cylinder engine comprising a stator having a double cam track, one track comprising opposed portions which project substantially beyond the adjacent portion ot the other track, a rotor comprising offset cylinders having opposing pistons, and rollers on' said pistons, the adjacent rollers being disposed to follow different tracks throughout the rotation ot the rotor, substantially as described.

22. A rotary cylinder engine as described in claim 21, in which the two t 1acks comprise similar sharply inclined curved portions disposed to stand opposite all the pistons at the moment of their power stroke.

23. A rotary cylinder engine as described in claim21, in which the tracks have portions lying in the same curved planes connecting their relatively oiiset portions.

24. A rotary cylinder engine as described in claim 21, in which the track following the minor axis s provided with opposed curved `zones concentric with therotor axis and disposed to hold the pistonswhile traversing 1t in extreme inward position.

25. In amotor, a stator having cam tracks,

llO

a rotor having two parallel cylinders closed at their outer ends and offset on each side ofthe motor axis, two opposed pistons in each cylinder with piston rods reciprocating through the closed ends of the cylinders, each diametrically opposite pair otl pistons 'engaging through suitable bearings, a separate track, each track forming a system of curved cams arranged to control the opposed pistons in each cylinder and comprising four similarly and sharply curved zones disposed opposite the pistons during their power strokes.

26. A rotating cylinder engine as defined in claim 4, in which means are provided to form an air cushion to take the momentum and centrifugal force of the pistons on their outward stroke to utilize the same to co-operate with the track in starting the pistons on their inward stroke. n

27. A rot-ary cylinder engine according to claim 1, in which the cross heads of co-acting pistons are of different lengths and in which lcam tracks of different curvilinear conformation are provided for the rollers on said dierent cross heads, the sections of the track for the rollers on the longer cross heads being spaced to allow the shorter cross heads and the rollers thereon to pass between said sections.

28. A rotary cylinder engine as described in claim l, in which two separate mixing chambers are provided between the said pair of cylinders comprising pressure controlled automatic valves regulating the admission of air and gas to said chambers, the discharge of the mixture therefrom into the cylinders, and the exhaust of gases from the cylinders through said chambers.

29. A rotary engine as described in claim l, in which the pistonsare mounted on piston rods having inwardly curved cross heads on their outer ends on which cross heads rollers are mounted, and in whichV the outer ends of the cylinders are closed and provided with f stuiiing boxes for the piston rods.

. 30. In a rotary cylinder engine, a rotor comprising an oset cylinder having its outer ends closed, opposing pistons operable in said cylinder, automatic pressure controlled mechanisms on each side of the axis oi' the engine and controlling a common teed of gas to the center of the cylinder, and an independent exhaust of gases from the ends ot the cylinder.

31. A rotary cylinder engine as described in claim l, in which the supply and exhaust means are symmetrically arranged at both ends of the cylinders.

32. A rotary cylinder engine as described in claim l, in which two gas supply and exhaustmeans comprise independent automat-ic elements which` are symmetrically disposed on each side of the axis of the engine between the said cylinders.

33. A rotary cylinder engine as described Y in claim 30, in which each of said mechanisms comprises a chamber having gas intake portsat its inner end and gas exhausts ports at its outer end, and cylinder exhaust ports entering an intermediate Zone, there being an automatic pressure controlled valve movable in the chamber to both modify the pressure on the mixture therein and to control the communication between the several exhaust ports entering it.

34. A rotary cylinder engine as described in claim 30, in which each of sai'd'mechanisms comprises a chamber having gas intakeports at its inner end and gas exhaust ports at its outer end, and cylinder exhaust ports entering an intermediate zone, there being an automatic pressure controlled valve movable in the chamber t0 both modify the pressure on the mixture therein and to control the communication between the several exhaust ports entering it, in which said floating valve is operated by a piston exposed to the pressure trapped at the extreme outer end of the engine cylinder and moved thereby to increase the pressure on the mixture at the inner end of said chamber.

35. In a rotary cylinder engine, a rotor comprising a cylinder having opposing pistons therein, a stator having cam tracks with vwhich the outer ends of the pistons co-act,

In testimony whereof I aiiix my signature.

GEORGE EDGAR BRAGG.' 

